Pneumatically-operated musical instrument.



F. MORITZ. PNEUMATIGALLY OPERATED MUSICAL INSTRUMENT. APPLICATION FILED NOV. 17, 1911.

Patented Aug. 25, 1914.

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P. MORITZ. PNEUMATIOALLY OPERATED MUSICAL INSTRUMENT. APPLIOATION FILED NOV. l7 1911.

1,1 08,385 Patented Aug. 25, 1914.

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FRIEDRICH PNEUMATICALLY-OPERATED MUSICAL Application filed November 17, 1911.

To all whom it may concern Be it known that I, FRIEDRICH Monrrz, a subject of the German Emperor, and residing at Dortnnunl. Germany, have invented certain new and useful Improvements in PneiunaticallyOperated lllusical Instruments, of which the following is a specification.

My invention relates to pneumaticallyoperated musical instrun'ients, and a pri" mary object is to provide a device by means of which one single note of a group of notes can be rendered conspicuous. end by subdividing the bellows used for producing the notes into two chambers, each of which can be influenced b a perforation in trackers, one of the chambers being used for producing ordinary notes, while the second is simultaneously used with the first for producing conspicuous notes. By arranging two evacuated chambers which are fed by the common principal magazine and 7 whose vacua can be relatively varied by the player it is possible to vary in strength the note which is to be rendered conspicuous from the other notes.

Several illustrative embodiments of my invention in combination with one of the well-known control valve mechanisms are represented by way of example in the accompanying drawings, wherein Figure 1 is a vertical section showing a control valve mechanism for sounding notes to be provided for each individual note, Fig. 2 a top plan view of the bellows after the control valve mechanism has been removed, and Fig. 3 a cross-section taken on the line A E in Fig. Fig. 1 is section, enlarged, through a simple valve and Fig; 5 is a like view through a double valve; Figs. 6, 7 and 8 respectively correspond to Figs. 1, 2 and 3 and show another illustrative embodiment; Fig. 9 is a cross-section through the sliding block, and Figs. 10 and 11 are elevations showing two forms of the latter; Figs. 12 and 13 show examples of the perforation requisite for the sliding block according to Figs. 10 and 11.

Ordinary notes or groups of notes are sounded in Well-known manner by evacuating a bellows controlled by the opening of the well-known perforations in trackers by the control valve system. The trackers 1 possess for each individual note a perforation 2 from which a tube 3 leads to the rear of a diaphragm 4. The other side of the Specification of Letters Patent.

1 attain this MORITZ, OF DORTMUND, GERMANY.

INSTRUMENT.

Patented Aug. 25, 1914.

Serial No. 660,918.

diaphragm is connected with the wind-chest 5 which is evacuated by the principal maga- Zine. As long as the perforations 2 are covered by the note sheet (3 the same degree of vacuum exists upon. both sides of the diaphragm 1, because the pressure in the wind-chcst 3 is communicated to the other side of the diaphragm through the so-called bleed-hole 7. Connected with the diaphragm 4: is a valve 8 which in the rest po 'sition of the diaphragm closes the windchest owing to its being seated on the hood Slof the bellows 10. hen the perftn'ations 2 are uiu'rovered by the perforations in the note sheet (3 air passes to behind the diaphragm 4 and distends the same, whereupon the valve 8 closes the admission port 11 for air to the bellows and the chamber 5 is con 'nected by way of the channel lows 10. As soonv as the bellows is evacuated it collapses and through the medium of levers and rods depresses the key.

According to my invention the bellows 10 is. subdivided by a partition 13 into two chambers 14'. and 15, of which only the chamber 14. causes an ordinary note to be sounded. The chamber 15 is controlled by a special control valve mechanism 16. In front of the main perforations 2 auxiliary perforations are provided for each individual note which are uncovered by enlarged holes 43 or 44. at the. same time as or immediately before the main holes 2 are opened. A tube 19 leads from the perforation 17 to the auxiliary control valve mechanism 16 having the bleed-hole 20. When the perforation 17 is covered by the note sheet, there exists on both sides of the diaphragm 16 in the additional wind-chest 21 the same degree of vacuum owing to the hole 20 and the valve 22 connected with the diaphragm shutting the wind-chest 21 off from the channel 23 and the chamber 10. This is then connected with the atmosphere throughthe channel 23 and the opening 24. In the chamber 15 is provided a freely moving valve 25 below an opening 26 which is conthe chamber 15 being also evacuated. When the note is sounded the air in the chamber 15 is driven out through the opening .24. As soon as the auxiliary perforation 17 is onened b an enlar ed hole 43 or air both its chambers. Bv means of this device passes to behind the diaphragm 10 whereby this is reversed and the opening 24: closed. The vacuum oil. the wind-chest 21 is then transferred to the chamber 15, but cannot operate there as long as air can pass through the opening 11, channel 12, chamber 141, channel 27 and the opening 26 at the opened valve 25. Shortly afterward, possibly simultaneously, the main pertlforation 2 opened by the holes -Ll-3 or aid, the valve 8 is hereby reversed, the opening 11 closed and the chamber 14. evacuated. A vacuum is 110w formed in the chamber 15 and the bellows is ope 'ated by both. chambers simul taneously and with increased force.

In the form ust (flescribed the wind-chests 5 and 21 are connected one with the other so that a higher degree of vacuum may be used in 21 than that used in 5.

In theform shown in 6, 7 and S and in order to prevent changes in the pressure in the lower vacuum chamber by means of the higher vacuum of the other chamber through the channel 27, a second valve 30 is provided, in addition to the said valve 29 being loosely connected to the lever for the purpose; both valves are mounted on an unequal armed lever in such a way that the valve 29 has a loose connection with the lever and can rest on its seat independently of the movement of the lever. This takes place as soon as the vacuum existing in the chamber 1 1 acts on the valve when an ordinary note is sounded. As soon as the valve is closed the lever is relieved of the weight of the valve and the valve 30 drops, in consequence of its own weight assisted by the superior Weight of the longer lever arm, down out of its box 33 on to its seat 31. In this improved double chambered pneumatic the auxiliary chamber is shut oil by a self closing valve when an ordinary note is to be played, but for an accentuated note the auxiliary chamber is first exhausted mid then the main chamber is exhausted, the ex hausting oi the auxiliary chamber, however, having no eiiiect until the main chamber is exhausted. Thus when an accentuated note is struck the chamber 15 is first exhausted without its being able to operate, because air can pass not only through the channel 27 and the port 31 of the valve 30 which is held from closing by the cap 33, by reason of the fact that the cap prevents the action of the outflowing air but also through the slot 32 leading to the atmosphere. It the chamber 14 is now also evacuated. the valve 29 is at once seated by reason oi. the suction created and the two-armed lever 28 is relieved. The valve 30 now falls owing to its own weight and is seated in consequence of the flow of the air entering through the slot 32, where by the chamber 15 is shut oil from the atmosphere and the bellows is operated by it is possible to render one single note conspicuous with a non-throttled vacuum from the wind-chest 21, when the wind-chest 5 is hrottled while playing the piano.

The valves which. must operate very rapidly and accurately on account of the lightness of the bellows consist of a bell or cupshaped piece of sheet metal having rounded ed gcs, preferably thin. aluminium, loosely connected with the valve rod by a muff (the bell 35 is covered by a disk of india-rubber 38 or similar material of larger diameter than the bell and connected by an inner collar 35.) with the metal. Should the valve be seated slantwise the overlapping edge of the disk of lIlClltt-l'llbbfll' 38 is seated tightly on the seat which can be provided with a cushion 1-0 of india-rubber or the like for preventing the edge ol. the bell striking through. In the double seated valve accord- .ing to Fig. 5 two bells are arranged one over another, a buffer or disk 4L5 being preferably placed. between them.

In the form of thetrackers 1 shown in the drawing the auxiliary perforation 1'1" is provided with an advance bleed-hole '11 through which the admission ol free air is to be eli ected, owing to the small section oi the perforations 1?, the said advance bleedhole 11 equalizing the suction action brought about by the bleed-hole 20 of like section until the diaphragm is reversed owing to the auxiliary perforation 17 being fully opened. T he auxiliary perforations are located laterally of the principal perforations and are either undivided on one side according to Fig. 10, or divided at the two sides in :lront of the main perforations according to Fig. 11. The perforations in the note sheet for striking conspicuous notes are larger than the perforations 1-2 for sounding ordinary notes. Corresponding to the holes in the trackers according to Figs. 10 or 11 the new perforation has an angular shape according to Fig. 12, or the shape of a square 414: which. may be substituted by a trapezoid or by a reduced rectangle. A great advantage of the new perforation is that existing note sheets can be'made usable for the new device by making additional holes and without. any further alteration by the player himsel'l ln the trackers 1 the auxiliary perforations lead to holes 18 which are bored from the one longitudinal side into the trackers. The tubes 19 can therefore be connected without di'llicultv laterally oi the row of tubes 3 to the holes 18.

1 ne described control valve mechanism is onlv an example for elucldating the invention and may be substituted by any other well-known control valve mechanisms.

1. The combination with a pair of wind chests; of a bellows provided with a parti' tion dividing the bellows into two chambers, each of said chambers having a passage leading therefrom and communicating with the atmosphere, and valves controlling respective passages and being in turn controlled by pressure conditions in the respective wind chests.

2. In a device of the kind described, a bellows provided with a partition dividing 1o said bellows into a pair of chambers, said bellows being provided with passages leading from respective chambers to the atmosphere, valves controlling said passages, a lever pivoted intermediate its ends and carrying 1L one of said valves, the remaining valve being movably connected to said lever for independent limited movement with relation to the lever, and means to control the action of said valves.

if? 3. The combination with a pair of wind chests, of a bellows provided with a partition dividing the same into two chambers, separate passages connecting said wind chests with said chambers, said passages having connections leading to the atmosphere, and pneumatically operated valves for controlling the communication between said passages and said wind chests or the atmosphere.

4. The combination with a pair of Wind 30 chests, of a bellows provided with a partition dividing the same into two chambers, separate passages connecting said wind chests with said chambers, said passages having connections leading to the atmos- 35 phere, pneumatically operated valves for controlling the communication between said passages and said wind chests or the atmosphere, means forming a passage between said chambers, and a quick acting non-re- 40 turn valve adapted to control said passage.

5. A pneumatic instrument comprising in combination, a bellows provided with a partition dividing said bellows into a pair of chambers, means providing a passage 45 connecting said chambers, a quick acting automatic non-return valve for controlling said passage, and means for varying the air tension in said chambers.

CHARLOTTE SOMMER, ALBERT NUFER.

Copies of this potent may be obtained for live cents each, by addressing the Commissioner of Yatente. Washington, D. 0. 

